Process for manufacture of phenolated fatty acids



3,074,983 PROCES FOR MANUFACTEJRE 6F PHEN'QLATED FATTY ACZDS Fred G. Barrett and Charles G. Goebel, (Iincinnati, Ohio, assignors to Emery industries, inc, Cincinnati, Shin, a corporation of Ohio No Drawing. Filed Apr. 26, 1961, Ser. No. 105,549 8 Claims. (Ci. 260413) This invention relates to a method of producing a non-ester addition product of a phenolic compound and an unsaturated fatty acid.

Condensation of an aromatic compound with an unsaturated fatty acid occurs at a double bond of the acid and involves addition of a hydrogen atom to one of the unsaturated carbon atoms of the acid and of the aromatic residue to the other carbon atom. The condensation product is essentially a straight chain aliphatic acid with an aromatic side chain.

The condensation of an unsaturated fatty acid and a phenolic compound results in products having unusual properties in that they contain both hydroxyl and carboxyl groups. The presence of these groups in the reacting ingredients poses a manufacturing problem in that the hydroxyl group of the phenolic compound tends to react with the carboxyl group of the unsaturated fatty acid to form a phenolic ester rather than the desired addition compound. To overcome this tendenc, the practice heretofore has been to react the phenolic compound with a methyl or other lower alkyl ester of the unsaturated acid. With the carboxy group already esteritied, the problem of phenolic ester formation does not exist. However, the resulting product is unattractive since it contains but one reactive group, i.e., OH. The methyl or other ester-linked radical in the product may later be removed from the addition product by hydrolysis, but this is a difiicult and expensive operation.

In carrying out the above reaction between phenol compound and unsaturated acid ester, the practice has been to use catalysts such as clay, sulfuric acid, or a Friedel-Crafts catalyst such as aluminum chloride, boron trifluoride, or the like. When using a clay catalyst the practice has been to dry the clay prior to use, presumably to improve its effectiveness.

It is an object of this invention to provide a direct efficient method for the production of phenolated unsaturated fatty acids. A more particular object is to provide a method of this character which minimizes the simultaneous formation of the phenolic ester.

The nature of still other objects of the invention will be apparent from a consideration of the descriptive portion to follow.

We have discovered that when a phenolic compound selected from the group consisting of phenol and lower alkyl-substituted phenols is reacted with an unsaturated fatty acid of natural origin at temperatuers of about 125 to 200 C. in the continuing presence of a minor percentage of a crystalline clay mineral and of from about 0.5 to 2.5% of free water, i.e., that readily available as such and not present as water of hydration. Under these conditions, it has been found that the desired addition reaction, whereby a nuclear carbon atom of the phenolic compound becomes bonded to one of the unsaturated carbon atoms of the acid reactant, proceeds (to form) efiiciently with little concomitant formation of the corresponding ester compound or other loss of available carboxyl or hydroxyl groups in the respective reactants. Specifically, by practicing the reaction in this fashion the formation of phenolic ester is reduced to less than one-third the amount which would otherwise re sult under the most favorable conditions heretofore employed.

Amounts of water ranging from 5% to 2.5% based on the weight of the reactants, have been found to retard ester formation but not to significantly decrease the yield of the phenolic addition product. Water levels outside this range tend to interfere with the reaction and result in decreased yields as well as in other disadvantageous product characteristics. Optimum results are obtained as the total amount of free, or available water in the system is from 1.0 to 2.0%. The phenolic and acid reactants each normally contain about 0.10.2% available water. However, these amounts are disregarded in calculating the available water content of the system.

Any of the unsaturated fatty acids as found in the naturally occurring oils and fats may be employed in a practice of this invention. Representative acids are undecylenic, oleic, linolexic, linolenic, palm'itoleic and erucic acids as well as isomeric modifications of such acids. The mixed unsaturated acids which may be derived from cotton, soya, linseed oils or from other fats or oils containing a predominant amount of unsaturated acids may be employed and also tall oil fatty acids.

The phenolic reactant may be phenol itself, or one of the various derivatives thereof wherein the phenyl nucleus is substituted by one or more lower alkyl groups of from 1 to 4 carbon atoms such as methyl, ethyl, propyl, isopropyl, butyl or isobutyl. However, a preferred class of phenolic compounds for use in practicing the invention is made up of phenol and its methyl-substituted derivatives such as crcsol and xylenol.

The clay minerals which may be used in a practice of this invention are surface active clay minerals such as montmorillonite, hectorite, halloysite, attapulgite and sepiolite. The various montmorillonite-rich bentonites may also be used. In general, clay minerals of the montmorillonite type constitute a preferred class for use in the present invention. The amount of clay mineral employed in the reaction mixture may range from about 1 to 20%, based on the weight of the other reactants, though from a practical operating standpoint, a preferred range is from 2 to 10%.

As normally sold, most of the commercial clay minerals usefully employed in this process contain from about 10 to 20% of water as free water and not as water of hydration. Thus, depending on the amount of Water present in the particular clay and the proportions of clay utilized in the reaction system, the free water content of the clay will provide part or all of the necessary water.

In carrying out the reaction it is preferable to employ an excess of the phenolic compound to force the reaction to completion and then remove the excess of phenolic compound by vacuum distillation rather than to employ molar proportion or an excess of fatty acids, as the temperatures required to remove the unreacted fatty acides by distillation even under high vacuum are so high that the product tends to resinify.

The excess of phenolic compound insures practically complete reaction of the unsaturated fatty acid. The completeness of the reaction can therefore be determined either from the weight of the non-volatile residue or from that of the volatile, phenolic component. A normal non-volatile residue, but coupled with a higher than theoretical neutralization equivalent and a lower than normal hydroxyl value, is an indication that the phenolic compound and the unsaturated fatty acid have reacted but that considerable ester has formed as evidenced by the deficiency in hydroxyl and carboxyl groups.

The following examples illustrate the practice of the invention in various of its embodiments.

EXAMPLE 1 In the operations presented in this example, parts of oleic acid were reacted with 100 parts of cresol" in the presence of 10 parts of an acid-activated montmorillonite clay (Grade 1 Filtrol, a product of the Filtrol Corporation) and varying amounts of added water, as

the contents heated to 160-165 C., this temperature range was maintained for 4 hours. The contents of the autoclave were cooled, filtered and distilled to 150 C. under a pressure of 1 mm. Hg. The distillation residue indicated by the data presented in the table given below. amounted to 115 parts (85% of theory) and had a neu- In Run 1 thereof, which is inserted for comparative purtralization equivalent of 405, asaponification equivalent of poses, the clay used was first predriedand contained es 368, and a hydroxyl value of 102. sentially no free Water. In the other runs the clay used contained from 1215% of available Water. Each run EXAMPLE 4 was conducted by placing the reactants in a stirred auto- Fatty acids P from the rectification of crude clave which was then closed, brought to the 160 C. tah0i1fattYaCidS,Pheh01(100 P and Grade 1 Filtrol reaction temperature and maintained thereat for 4 hours. p which Contained 1215% of fret: Water, Were At the conclusion of each run, the autoclave was cooled, heated (after purging With Carbon dioxide) a rocking opened, and the product distilled at200 C. at 20 mm. yp autoclave for 4 hours at The Contents Of Hg to remove unreacted cresol. The remaining, the autoclave were cooled, filtered and di-stilled'as devolatilized product was when weighed and analyzed to described in Example 2. Phenolated tall oil fatty acids (66.7 termine its neutralization equivalent (N.E.), saponificaparts) Of trali ati n equivalent 23, saponfication tion equivalent (5.15.) and hydroxyl value. The ester equivalent 386, and hydroxyl value 110 where obtained as content of the product was calculated from the NE. and still residue. S.E. values, and data allied thereto. EXAMPLE 5 Table In this operation 200 grams of symmetrical Xylenol Runs showing reaction of cresol with oleic acid in preswere reacted with a like amount of oleic acid in the ence of clay mineral at varying water levels. presence of 20 grams of an acid-activated montmorillonite Added H3O Yield of Ester Run (percent Total H2O non-volt Hydroxyl (percent No. Clay based on in system tile prod. NE. SE. value calcutotal (percent) (percent lated) charge) of theory) Theoretical values 100 390 390 144 0 Predried. 0 0 -0.2 102.5 450 37 114 17 N 0 0. 6-0. 75 99 435 373 114 14 0.5 1 -1.25 08 410 371 120 9.3 1.0 1.6-1. 75 96 402 366 116 9.2 1.5 2. 1-2. 93 390 305 10s as 2.0 2. 62. 75 88 376 351 82 6.9

The results obtained in Run 1 above, conducted in the clay mineral (Grade 20 Filtrol) containing approximately absence of water, indicate the product formed contained 0 12% available water. The reaction Was conducted in a a relatively large proportion of ester. Conversely, Run small, rocking type autoclave for 3 hours at 160 C., a 6, which was also inserted for comparative purposes and pressure of 20-25 p.s.i.g. developing in the vessel as it was conducted in the presence of from about 2.6 to 2.75% reached reaction temperatures. At the end of the reaction of free Water, shows that the yield of the desired addition period the Xylenol and unreacted'acids were removed from product is rapidly falling off (as has the hydroxyl value), the product by distillation at 2-3 mm. Hg, leaving a nonwhen the values are compared with those of Run 5 where volatile resdue in a theoretical yield of 70%. This residue the total free Water content Was about 2.1 to 2.25%. Run had a NE. of 460 (theory equals 404), an acid value of 2, conducted without water other than that naturally 122, a SE. of 385 and a hydroxyl value of 110 (theory present in the clay, though not run under the most favorequals 139). able conditions, gave results which were significantly The phenolate-d fatty acids of the type which are probetter than those obtained in (dry) Run 1, thus supporting duced by the practice of the method of this invention the fact that at least 0.5 weight percent of free Water may be used for a variety of industrial purposes such as should be present in the system. anti-oxidants, corrosion inhibitors, anti-rust compounds,

EXAMPLE 2 and oil additives.

V We claim:

100 Parts of 01310 acid and Parts Of cresol Were 1. A method for the production of'addition products of heated ill a glass flask q pp With stirrer, thel'ometei a phenolic compound and an unsaturated fatty acid which and walef'cooled reflux condenser arranged to rehlfh comprises, reacting at least one fatty acid selected from dehsed Water to the flash, the System also whtaihing 10 the group consisting of undecylenic, oleic, linoleic, lino- Parts Of Grade 1 Filtrol, the frae Water Content Of which lenic, palmitoleic and erucic acids with a phenolic comhad been increased to Heating in the flask pound selected from the group consisting of phenol and tihhed 4 hours at With agitation The P lower-alkyl substituted phenols, said reaction being conhct of the Teactioh Was Coolsd aPPYOXimatBIY ducted in the continuing presence of a minor percentage the Filtrol removed by filtration and unreactcd cresol reof a surface active clay mineral and of from about 0.5 to moved by distillation under 20 mm. vacuum at a tem- (35 2.5% of available Water, at temperatures of from about perature of 200 C. The resulting product, recovered to 200 C. in the amount of 138.4 parts, or 100% of theory, showed 2. A method for the production of addition products by titration a neutralization equivalent of 428 and a hyof a phenolic compound and an unsaturated fatty acid droxyl value of 117. 7 which comprises, reacting at least one fatty acid selected EXAMPLE 3 7 from the group consisting of undecylenic, oleic, linoleic,

Commercial grade oleic acid (100 parts), cresol (100 parts) and Grade 1 Filtrol (10 parts) containing 12-15 free water, were processed in a stirring type autoclave. The autoclave was purged of air with carbon dioxide and linolenic, palmitoleic and erucic acids with an excess, over the stoichiometrically required amount, of a phenolic compound selected from the group consisting of phenol and lower-alkyl substituted phenols, said reaction being conducted in the continuing presence of from 1 to 20% of a 5 clay mineral of the montmorillonite type and of from about 0.5 to 2.5% of available water, at temperatures of from 125 to 290 C.

3. The process of claim 2 wherein there is added the step of distilling off the excess of the phenolic reactant to obtain the desired addition product as the distillation residue.

4. A method for the production of addition products of a phenolic compound and an unsaturated fatty acid which comprises, reacting at least one fatty acid selected from the group consisting of undecylenic, oleic, linoleic, linolenic, palmitoleic and erucic acids with an excess, over the stoichiometrically required amount, of a phenolic compound selected from the group consisting of phenol and lower-alkyl substituted phenols, said reaction being conducted in the continuing presence of from 1 to 10% of a clay mineral of the montmorillonite type and of from about 1 to 2% of available Water, at temperatures of from 125 to 200 C.

5. The process of claim 2 wherein the phenolic reactant is phenol.

6. The process of claim 2 wherein the phenolic reactant is cresol.

7. The process of claim 2 wherein the phenolic reactant is xylenol.

8. The process of claim 2 wherein the fatty acid reacted with the phenolic compound comprises a mixture of fatty acids as distilled from tall oil.

No references cited. 

1. A METHOD FOR THE PRODUCTION OF ADDITION PRODUCTS OF A PHENOLIC COMPOUND AND AN UNSATURATED FATTY ACID WHICH COMPRISES, REACTING AT LEAST ONE FATTY ACID SELECTED FROM THE GROUP CONSISTING OF UNDECYLENIC, OLEIC, INOLEIC, LINOLENIC, PALMITOLEIC AND ERUIC ACIDS WITH A PHENOLIC COMPOUND SELECTED FROM THE GROUP CONSISTING OF PHENOL AND LOWER-ALKYL SUBSTITUTED PHENOLS, SAID REACTION BEING CONDUCTED IN THE CONTINUING PRESENCE OF A MINOR PRECENTAGE OF A SURFACE ACTIVE CLAY MINERAL AND OF FROM ABOUT 0.5 TO 2.5% OF AVAILABLE WATER, AT TEMPERATURES OF FROM ABOUT 125 TO 200* C. 